Dry desulfurization tower bottom ash discharge device for CFB (circulating fluidized bed)

Abstract

The utility model belongs to the field of desulfurization and ash discharge, and particularly relates to a CFB (circulating fluidized bed) dry desulfurization tower bottom ash discharge device which comprises an absorption tower inlet section, and a discharge tank is mounted at the bottom of the absorption tower inlet section; a double-shaft spiral ash discharge machine is omitted, the discharge groove is only arranged at the bottom of the inlet section of the absorption tower, a certain number of purges are arranged on the tower bottom plate of the inlet section of the absorption tower and the side plate of the discharge groove at intervals, and compressed air is intermittently and circularly blown through the blowing end seat, so that ash accumulation and hardening at the tower bottom plate of the inlet section of the absorption tower and the discharge groove can be effectively prevented; the height of the discharge groove can be adjusted according to the distance between the inlet section of the absorption tower and the ground, and the discharge groove is matched with a pneumatic gate valve and a duplex heavy hammer flap valve to discharge ash, so that the problem that ash cannot be discharged smoothly when the mounting height of the inlet section of the absorption tower exceeds 2.5 m can be effectively solved; and the environmental pollution problems such as dust overflow and accumulation on the ground and the periphery of the tower bottom during long-term operation due to flying dust generated in the ash discharge process can be effectively prevented.

Description

Technical Field

[0001] The utility model relates to the field of desulfurization and ash discharge, in particular to a CFB circulating fluidized bed dry desulfurization tower bottom ash discharge device. Background Art

[0002] Circulating fluidized bed CFB dry desulfurization has the advantages of simple operation, small footprint, low investment cost, and dry materials throughout the process. At present, this process is increasingly used in the engineering applications of steel sintering and pelletizing industries; however, the blockage of desulfurization circulating ash has become a key factor in determining whether the desulfurization system can be put into normal operation. The process principle is that the flue gas drawn from the sintering main exhaust fan enters the bottom of the absorption tower, and after being accelerated by the Venturi structure of the absorption tower, it reacts with the added absorbent (slaked lime), circulating ash and water to remove various pollutants such as NOx, SO2, SO3, HCl, HF, heavy metals, etc. in the flue gas, among which the SO2 emission concentration is ≤35mg / Nm3. At the same time, in order to achieve the optimal reaction temperature, the flue gas temperature is cooled to a dew point temperature of 15-20℃ or above by spraying water into the absorption tower. The flue gas carrying a large amount of absorbent, adsorbent and reaction products enters the desulfurization bag-type dust collector from the top of the absorption tower downward for gas-solid separation. The dust emission concentration of the flue gas after gas-solid separation is ≤5mg / Nm3; most of the desulfurization ash collected by the bag-type dust collector continues to return to the absorption tower for circulation through the return chute, and a small amount of ash is pneumatically transported to the desulfurization ash storage.

[0003] At the inlet section of the absorption tower, when there is ash accumulation at the bottom of the tower, the fallen ash needs to be discharged through the ash discharge device at the bottom of the tower. The commonly used ash discharge device at the bottom of the tower is composed of a double-axis spiral ash discharger at the bottom of the tower, a pneumatic plug valve, and a double-weight flap valve. When the main engine load fluctuates and the flue gas volume becomes smaller, the air volume is not enough to support the material in the tower, and ash will fall at the bottom of the tower. When there is ash accumulation at the bottom of the tower, the fallen ash needs to be discharged through the ash discharge device at the bottom of the tower to avoid clogging the inlet section and affecting the normal operation of the system.

[0004] When the height of the tower bottom plate is less than 2.5m from the ground, the configuration scheme of tower bottom ash discharger, pneumatic gate valve and double heavy hammer flap can be adopted; however, when the height of the tower bottom plate exceeds 2.5m from the ground, since the discharge port is higher than the ground, it is not convenient to place ton bags or carts at the discharge port, and there is a certain space between the discharge port and the ton bags or carts. The ash discharge process will generate dust, and during long-term operation, dust will overflow and accumulate on the ground and around the bottom of the tower, polluting the environment. Therefore, when the bottom of the tower is higher than the ground, the ash discharge problem needs to be solved urgently. Utility Model Content

[0005] (I) Purpose of the utility model

[0006] In order to solve the technical problems existing in the background technology, the utility model proposes a CFB circulating fluidized bed dry desulfurization tower bottom ash discharge device, which has the characteristics of smooth ash discharge and dust prevention.

[0007] (II) Technical solution

[0008] In order to solve the above technical problems, the utility model provides a CFB circulating fluidized bed dry desulfurization tower bottom ash discharge device, comprising an absorption tower inlet section, wherein a discharge trough is installed at the bottom of the absorption tower inlet section;

[0009] The purge mechanism comprises a purge device, which is mounted on the side wall of the absorption tower inlet section and the discharge tank through a fixing frame, the outside of the purge device is connected to the air intake device, and one end of the purge device penetrating the absorption tower inlet section and the discharge tank is installed with a purge end seat with a nozzle;

[0010] A pneumatic gate valve is installed at the outlet end of the discharge trough, and the other end of the pneumatic gate valve is connected to a double-weight flap valve.

[0011] Preferably, the discharge trough and the contact section of the absorption tower inlet section are provided with a plurality of openings with a width of 500 mm, and the length of the discharge trough is the same as the width direction of the absorption tower inlet section.

[0012] Preferably, the purge devices are arranged at intervals at the bottom plate of the absorption tower inlet section and at the side wall of the discharge trough.

[0013] Preferably, the pneumatic gate valve is provided with a cylinder, a movable piston rod is installed at the output end of the cylinder, and the other end of the piston rod is connected to a gate piece that blocks the outlet end of the discharge groove.

[0014] Preferably, the double weight flap valve has a built-in rotatable shaft rod, and the shaft rod is sleeved with a flap member for blocking the channel of the double weight flap valve.

[0015] The shaft rod is also connected with a handle which passes through the groove on the side wall of the double-weight flap valve.

[0016] The above-mentioned technical scheme of the utility model has the following beneficial technical effects: the double-axis spiral ash discharger is eliminated, and only a discharge trough is set at the bottom of the inlet section of the absorption tower, and a certain number of purge devices are arranged at intervals between the tower bottom plate and the side plate of the discharge trough of the inlet section of the absorption tower. The external air source inputs compressed air through the air inlet section of the purge device, and intermittently circulates and sprays it through the purge end seat, which can effectively prevent ash accumulation and compaction at the tower bottom plate and the discharge trough of the inlet section of the absorption tower. The height of the discharge trough can be adjusted according to the height of the inlet section of the absorption tower from the ground, and the ash is discharged in conjunction with the pneumatic plug valve and the double heavy hammer flap valve, which can effectively solve the problem that the ash cannot be discharged smoothly when the installation height of the inlet section of the absorption tower exceeds 2.5m, and can effectively prevent the dust from being generated in the ash discharge process, and the environmental pollution problems such as dust overflow and accumulation on the ground and around the bottom of the tower during long-term operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the structure of the utility model;

[0018] Figure 2 This is a front view structural schematic diagram of the utility model;

[0019] Figure 3 It is a side view structural schematic diagram of the utility model;

[0020] Figure 4 It is a schematic diagram of the structure of the double-weight flap valve of the utility model.

[0021] Reference numerals:

[0022] 1. Inlet section of absorption tower; 2. Discharge trough; 31. Pneumatic gate valve; 32. Cylinder; 33. Piston rod; 34. Gate member; 41. Double-weight flap valve; 42. Shaft rod; 43. Handle; 44. Flap member; 51. Purge device; 52. Air inlet end; 53. Fixed bracket; 54. Purge end seat. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail below in combination with specific implementation methods and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the utility model. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the utility model.

[0024] like Figure 1-4 As shown, the utility model proposes a CFB circulating fluidized bed dry desulfurization tower bottom ash discharge device, comprising an absorption tower inlet section 1, and a discharge trough 2 is installed at the bottom of the absorption tower inlet section 1;

[0025] The purge mechanism includes a purge device 51, which is mounted on the side walls of the absorption tower inlet section 1 and the discharge tank 2 through a fixing frame 53, the outside of the purge device 51 is connected to the air intake device, and a purge end seat 54 with a nozzle is installed at one end penetrating the absorption tower inlet section 1 and the discharge tank 2;

[0026] A pneumatic gate valve 31 is installed at the outlet end of the discharge tank 2 , and a double-weight flap valve 41 is connected to the other end of the pneumatic gate valve 31 .

[0027] It should be noted that: the contact section between the discharge trough 2 and the absorption tower inlet section 1 is provided with several openings with a width of 500 mm, and the openings are used to discharge the ash at the bottom plate of the absorption tower inlet section 1. The length of the discharge trough 2 is the same as the width direction of the absorption tower inlet section 1, so that the ash can be discharged over a large area.

[0028] In this embodiment, the double-axis spiral ash discharger is eliminated, and only the discharge trough 2 is set at the bottom of the absorption tower inlet section 1, and a certain number of purge devices 51 are arranged at intervals between the tower bottom plate of the absorption tower inlet section 1 and the side plate of the discharge trough 2. The compressed air is input by the external air source through the air inlet section of the purge device 51, and is intermittently circulated and sprayed through the purge end seat 54, which can effectively prevent the accumulation and compaction of ash at the tower bottom plate of the absorption tower inlet section 1 and the discharge trough 2. The height of the discharge trough 2 can be adjusted according to the height of the absorption tower inlet section 1 from the ground, and the ash is discharged in conjunction with the pneumatic plug valve 31 and the double hammer flap valve 41, which can effectively solve the problem that the ash cannot be discharged smoothly when the installation height of the absorption tower inlet section 1 exceeds 2.5m, and can effectively prevent the dust from being generated in the ash discharge process, and the environmental pollution problems such as dust overflow and accumulation on the ground and around the bottom of the tower during long-term operation.

[0029] The purge devices 51 are arranged at intervals at the bottom plate of the absorption tower inlet section 1 and the side wall of the discharge trough 2; the input compressed gas purges the internal dust to loosen the accumulated dust, making it easier for the dust to fall.

[0030] As a working example of the pneumatic gate valve 31: the pneumatic gate valve 31 is provided with a cylinder 32, and a movable piston rod 33 is installed at the output end of the cylinder 32, and the other end of the piston rod 33 is connected to a gate piece 34 that blocks the outlet end of the discharge groove 2; the cylinder 32 drives the piston rod 33 to contract, and the gate piece 34 moves to switch the channel connecting the discharge groove 2 and the cylinder gate valve 31 to a through state, so that the ash falls.

[0031] As a working example of the double weight flap valve 41: the double weight flap valve 41 has a built-in rotatable shaft 42, and a flap member 44 is sleeved on the shaft 42 to block the channel of the double weight flap valve 41; when the flap member 44 moves, the inclined channel of the double weight flap valve 41 is in an open state, and the upper and lower flap members 44 move at the same time to open the channel, thereby facilitating the falling of ash.

[0032] In order to facilitate the rotation of the shaft 42 , further, the shaft 42 is connected with a handle 43 which passes through the groove of the side wall of the double-weight flap valve 41 .

[0033] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation on the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the claims attached to the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the attached claims, or the equivalent forms of such scope and boundaries.

Claims

1. A CFB circulating fluidized bed dry desulfurization tower bottom ash discharge device, characterized in that: It comprises an absorption tower inlet section (1), wherein a discharge trough (2) is installed at the bottom of the absorption tower inlet section (1); The purge mechanism comprises a purge device (51), the purge device (51) being mounted on the side walls of the absorption tower inlet section (1) and the discharge trough (2) via a fixing frame (53), the outside of the purge device (51) being connected to an air intake device, and a purge end seat (54) having a nozzle opening being mounted on one end penetrating the absorption tower inlet section (1) and the discharge trough (2); A pneumatic gate valve (31) is installed at the outlet end of the discharge trough (2), and the other end of the pneumatic gate valve (31) is connected to a double-weight flap valve (41).

2. The ash discharging device at the bottom of a CFB circulating fluidized bed dry desulfurization tower according to claim 1 is characterized in that: The contact section between the discharge trough (2) and the absorption tower inlet section (1) is provided with a plurality of openings with a width of 500 mm, and the length of the discharge trough (2) is the same as the width direction of the absorption tower inlet section (1).

3. The ash discharging device at the bottom of a CFB circulating fluidized bed dry desulfurization tower according to claim 1, characterized in that: The purge devices (51) are arranged at intervals on the bottom plate of the absorption tower inlet section (1) and on the side wall of the discharge trough (2).

4. The ash discharging device at the bottom of a CFB circulating fluidized bed dry desulfurization tower according to claim 1, characterized in that: The pneumatic gate valve (31) is provided with a cylinder (32), the output end of the cylinder (32) is provided with a movable piston rod (33), and the other end of the piston rod (33) is connected to a gate piece (34) for blocking the outlet end of the discharge groove (2).

5. The ash discharging device at the bottom of a CFB circulating fluidized bed dry desulfurization tower according to claim 1, characterized in that: The double-weight flap valve (41) has a rotatable shaft (42) built in, and a flap member (44) for blocking the passage of the double-weight flap valve (41) is sleeved on the shaft (42).

6. The ash discharging device at the bottom of a CFB circulating fluidized bed dry desulfurization tower according to claim 5, characterized in that: The shaft rod (42) is also connected to a handle (43) which passes through a groove in the side wall of the double-weight flap valve (41).

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